{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T09:17:02Z","timestamp":1778663822505,"version":"3.51.4"},"reference-count":36,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,9,5]],"date-time":"2021-09-05T00:00:00Z","timestamp":1630800000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2017YFB1300302"],"award-info":[{"award-number":["2017YFB1300302"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81630051"],"award-info":[{"award-number":["81630051"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61976152"],"award-info":[{"award-number":["61976152"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81801787"],"award-info":[{"award-number":["81801787"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Young Elite Scientist Sponsorship Program by CAST","award":["2018QNRC001"],"award-info":[{"award-number":["2018QNRC001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Transcranial focused ultrasound (tFUS) has great potential in brain imaging and therapy. However, the structural and acoustic differences of the skull will cause a large number of technical problems in the application of tFUS, such as low focus energy, focal shift, and defocusing. To have a comprehensive understanding of the skull effect on tFUS, this study investigated the effects of the structural parameters (thickness, radius of curvature, and distance from the transducer) and acoustic parameters (density, acoustic speed, and absorption coefficient) of the skull model on tFUS based on acrylic plates and two simulation methods (self-programming and COMSOL). For structural parameters, our research shows that as the three factors increase the unit distance, the attenuation caused from large to small is the thickness (0.357 dB\/mm), the distance to transducer (0.048 dB\/mm), and the radius of curvature (0.027 dB\/mm). For acoustic parameters, the attenuation caused by density (0.024 dB\/30 kg\/m3) and acoustic speed (0.021 dB\/30 m\/s) are basically the same. Additionally, as the absorption coefficient increases, the focus acoustic pressure decays exponentially. The thickness of the structural parameters and the absorption coefficient of the acoustic parameters are the most important factors leading to the attenuation of tFUS. The experimental and simulation trends are highly consistent. This work contributes to the comprehensive and quantitative understanding of how the skull influences tFUS, which further enhances the application of tFUS in neuromodulation research and treatment.<\/jats:p>","DOI":"10.3390\/s21175962","type":"journal-article","created":{"date-parts":[[2021,9,6]],"date-time":"2021-09-06T13:18:26Z","timestamp":1630934306000},"page":"5962","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["The Effects of the Structural and Acoustic Parameters of the Skull Model on Transcranial Focused Ultrasound"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1362-3728","authenticated-orcid":false,"given":"Hao","family":"Zhang","sequence":"first","affiliation":[{"name":"Laboratory of Neural Engineering and Rehabilitation, Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanqiu","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin 300070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Minpeng","family":"Xu","sequence":"additional","affiliation":[{"name":"Laboratory of Neural Engineering and Rehabilitation, Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China"},{"name":"Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0676-3258","authenticated-orcid":false,"given":"Xizi","family":"Song","sequence":"additional","affiliation":[{"name":"Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shanguang","family":"Chen","sequence":"additional","affiliation":[{"name":"Laboratory of Neural Engineering and Rehabilitation, Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China"},{"name":"Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China"},{"name":"National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiqi","family":"Jian","sequence":"additional","affiliation":[{"name":"School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin 300070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong","family":"Ming","sequence":"additional","affiliation":[{"name":"Laboratory of Neural Engineering and Rehabilitation, Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China"},{"name":"Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,5]]},"reference":[{"key":"ref_1","first-page":"637","article-title":"Histology of Cerebral Lesions Produced by Focused Ultrasound","volume":"20","author":"Lynn","year":"1944","journal-title":"Am. 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